#include "apue.h"
#include <fcntl.h>

int main(int argc, char *argv[]){
    int val;
    if (argc != 2){
        err_quit("usage: argc error");
    }

    if ((val = fcntl(atoi(argv[1]), F_GETFL, 0)) < 0){
        err_sys("fcntl error for fd %d", atoi(argv[1]));
    }

    switch (val & O_ACCMODE)
    {
    case O_RDONLY:
        printf("read only");
        break;
    case O_WRONLY: 
        printf("write only");
        break;
    case O_RDWR:
        printf("read write");
        break;
    default:
        err_dump("unknown access mode");
    }

    if (val & O_APPEND){
        printf(", append");
    }
    if (val & O_NONBLOCK){
        printf(", nonblocking");
    }
    if (val & O_SYNC){
        printf(", synchronous writes");
    }
    putchar('\n');
    exit(0);
}